In communications networks, terminals may form a peer relationship with an associated gateway (e.g., an Internet protocol (IP) gateway) for a variety of purposes. Such purposes include enhancement of communications sessions over the network, such as the provision or utilization of security (e.g., IPsec) for communications links over the network, protocol acceleration (e.g., TCP performance enhancing proxies (PEP)), and data compression (e.g., IP header compression).
For network providers, a critical factor for commercial success is the level of reliability and quality of service provided to the various network subscribers. Network subscribers, for example, may range from individual consumer Internet subscribers to enterprise subscribers (including services and applications for communications between different corporate locations, such as a head office and various remote branch offices and teleworkers). Further, such enterprise subscribers may subscribe to a wide variety of applications and services (e.g., broadcast/multicast services, virtual private network (VPN) services, high speed Internet services and media streaming services, requiring a wide range of quality of service and reliability levels). In order to maintain the network services and functions, and to provide reliable communications and quality of service, to the various network subscribers, gateway availability becomes a significant and perhaps critical factor, because the gateway availability affects the services provided to a large number of terminals that are associated with and serviced by the gateway. One way of ensuring and improving gateway availability is to provide for gateway redundancy to cover for gateway outages and maintenance.
What is needed, therefore, is an approach for efficient, cost effective and reliable gateway redundancy that maximizes reliability and quality of service, while minimizing transitions between operational gateways and redundant backup gateways.